This Laboratory is designed so that grade school and middle school students, as well as people in general, can get to know the fascinating world of science and fluid mechanics. This Lab offers “fluid experiments” that you can enjoy using everyday materials around you.
The principles of phenomena related to fluid mechanics are often misrecognized, and there have been many mistakes in scientific books for a long time. Therefore, educators need to understand their misrecognition and correct principles. In this workshop, we will explain the basics of fluid mechanics through various experiments.
We continue to develop a micro wind power system such as horizontal and vertical axis turbines using open source CAE software, such xfrl5, Qblade and OpenFOAM. These open-source CAE software are not only cost-effective but also highly useful and having enough functionality for such development purposes. In this report, we present the flow of development process of the system and introduce how to use such open-source software during designing and evaluation processes. From experiences of utilization of them during R&D and students’ educations, it was confirmed that open-source CAE software are also very attractive for educating communication skills of students with foreign users and groups, which is important for global-working engineers today.
In Fukushima accident on 2011, after the loss of both the emergency core cooling system and IC core cooling, primary containment vessel (PCV) pressure increased. Water level measurement drifted because of water evaporation in the reference leg. Radiation level increased at a turbine building (T/B). There was a hydrogen explosion the after the suppression chamber (S/C) wet venting. By using the FCVS technology, the such the risk reduction during severe accidents in NPPs were attained. But owing to the global warming, the risk of natural hazards are increased, such as typhoon, hard rain, hot summer, severe snowfall, melt snow in north pole and south pole. It is very important to reduce CO2 emission by best mix of utilizing renewable energy and the safety enhanced nuclear power plants.
The advent of smart agriculture in Japan has resulted in significant labor productivity gains and increases in the quality of agricultural products through the active use of knowledge and techniques from a variety of fields, including ICT and robotics. ICT has been introduced to reduce the labor of water management, and at the same time achieve high quality cultivation. Several water management systems with ICT have already been commercialized and are in widespread use. In addition, we have nearly completed development of an autopilot transplanter, which will be made available commercially in the near future through technological transfer to agricultural machinery makers and has the following features: (1) rice planting, normally carried out by two persons, can be performed by one person feeding seedlings; (2) rice planting is automated except for the perimeter of fields; (3) paths need not be pre-programed; and (4) even compared to skilled operators, planting becomes more accurate with its high-speed turning and operation abilities.
The Low temperature differential Stirling engine for a craft workshop was improved. Fine adjustment during assembly is not necessary. Here, the explanation for attendees of a 5-hour-course craft workshop is shown by some pictures.
The flight trajectory of a soccer ball is strongly influenced by aerodynamic characteristics such as drag and lift coefficient. These characteristics are known to depend on the air flow around the ball and the vortex structure developed by that flow. This study aims to clarify the dominant vortex structures of a spinning soccer ball using a free flight test. In this study, we found that large-scale counter-rotating vortex pairs are one of the dominant vortex structures for a spinning soccer ball. The large-scale fluctuation of the side force on the spinning ball was also determined to be smaller than that on the non-spinning ball. These findings show that the flight trajectory of the spinning ball is regular and stable, and hence a curled shot or pass can be aimed precisely from the beginning of its course.
Detailed Earth History is recorded in the deep sea sediments distributed in the world ocean. The recent study on Earth history based on the micropaleontological and geochemical analysis of the deep sea sediments are introduced in this presentation.
The transistor technology is one of the fundamental technologies that support the information society. The transistor has been developed according to Moore's law over the past several decades. The transistor technology has been confronted with limitation of technology in many times, but engineers have overcome these limitations by developing various technical methods.
"Physical limit" is approaching that the transistor's line width becomes the level of atomic size. Transistor technology is stepping into areas where Moore's law cannot be applied. Several technical methods have also been proposed to overcome the physical limit. This paper outlines the history of transistor technology, and also introduces the direction of current technology.
Japanese railways are the most advanced in the world for safe, comfortable, accurate and dense operation. I will explain the technologies included in the railway vehicles that support this operation, and the features of the railway cars of East Japan Railway Company. In addition, I will introduce the important role of the Professional Engineer in railway vehicle design.
In the field of design, innovative ideation at the upstream stage of design process has been becoming important for making people’s life and society better as well as for being industrially competitive. In this paper, the author proposes a framework of collaborative intelligence for innovative design ideation utilizing inspiration of human intelligence and systematicity of artificial intelligence. In the framework, structure (S), function (F) and user experience (UX) of existing characteristic design examples are described as a design delta map and stored in the database. A software exhaustively estimates similarity of S, F and UX among design examples and presents pairs of design examples which may effective to trigger human ideation such as a pair of design examples where F’s are not similar but UX’s are similar between them. A Python implementation of the framework and some results of trials are presented to estimate effectiveness of the framework.
Titanium and titanium alloy have good combination of high mechanical properties and excellent corrosion resistance human body. So they have excellent properties for medical implants and medical devices.
The medical committee of the Japan titanium Society is supporting the activity that titanium and titanium alloys spread for medical application widely. It published the guide book of titanium for medical use, last year. The recent status for titanium application for medical use is described in this report.
World-wide demand of titanium for medical application was about 4,000～5,000 tons in 2017, it accounts for 3% of all titanium markets. In Japan, though shipment for titanium for medical use was 391tons, domestic use was 111 tons and it was only 28%.
Spine is widely used, and knee joint is follows in implant application.
Though titanium and titanium alloys are usually melted by VAR process, melting furnace to able to use recycle raw materials such as EBR or CCIM are recently used, too. Surface treatment to improve their bio-functionality has been actively investigated. Aluminum free low modulus titanium alloys researches to prevent bone shrinkages.
Commercially pure titanium(c.p.Ti) is used a lot for the plate heat exchanger and power plant condenser using the seawater. On the other hand, c.p.Ti is used for the building materials of the seaside part in the 1980s. By the development of the surface design materials and application technology, c.p.Ti is used for building in the urban area and the temple & shrine building. The latest applications to the field of architecture are showed.
In order to improve both the crash safety and the fuel efficiency, various shapes of thin-walled structures have been utilized as energy absorbers of automobiles based on the progressive buckling mechanism. In this study, the dynamic crushing behavior of metal honeycombs was studied with laying emphasis on the effects of strain rate, cell geometry and oblique impact on its energy absorption characteristics. Numerical models of some materials were made by considering the adhesive layer and the initial imperfection, and the strain rate dependence of honeycomb structure on the energy absorption capacity was discussed as compared with the corresponding experimental results. Furthermore, the branch angle of cell geometry and the crush angle were also varied to evaluate their effects. Oblique impact loading causes the transition from axial collapse to bending collapse, so that the mean buckling load at the crush angle of 45° was 30–50% smaller than that at the vertical angle.
To shorten the resin impregnation time of fiber metal laminate (aluminum alloy/GFRP laminates) during VaRTM process, mesh layers made of polyamide (PA) are inserted between aluminum alloy and GF layers. The resin impregnation experiment with fiber optic sensors has shown that the resin impregnation time is shortened due to the out-of-plane flow to the PA mesh via the circular holes in the metal layer which are introduced so that a resin distribution medium can be adapted to the VaRTM process for FML. The resin impregnation behavior was also clarified by control volume / finite element analysis. Drop-weight impact tests for the FMLs fabricated by VaRTM process show that higher energy is absorbed during impact loading by the laminates with the PA meshes inserted. This can be attributed to the interlaminar toughening between aluminum alloy and GFRP layers by inserting PA meshes.
Mechanical materials are roughly classified into three types, metallic materials, nonmetallic materials, and composite materials. Among them, zirconia is a kind of ceramics which is a nonmetallic inorganic material. Zirconia has some excellent properties, and it is known to be particularly excellent in mechanical strength, for that reason, it is often used as a structure. At present, zirconia is used as an optical communication component, various nozzles, crown materials, it is estimated that its use in medical applications will be expanded in the future. However, it can’t be said that the preparation process is completely controlled, and further improvement of mechanical properties is expected from now on by completely controlling.
Carbon Fiber Composite Cable (CFCC®) is a stranded carbon fiber reinforced plastic (CFRP), developed by Tokyo Rope Mfg. Co. Ltd. CFCC holds a superior property of the carbon fiber, in terms of high tensile strength, high tensile modulus, light weight, high corrosion resistance, non magnetic interact, and low linear expansion rate. The stranded construction of CFCC also gives high flexibility, which allows easy handling of the cable by shaping it into coil. The main applications of CFCC are civil works and overhead conductors. For example, CFCC has been installed as reinforcement of structures under corrosive environments such as oceans and acid hot-spring resorts. CFCC is also adopted as a core of high-temperature and low-sag overhead conductors because of its light weight. Owing to the superior features of CFCC, its applications to various fields have been increasing.
This paper presents the current status of the seismic safety enhancement for the pressurized water reactor (PWR) nuclear power plants of the Kansai Electric Power Co. (KEPCO). KEPCO made significant upgrades to seven units, including incorporating new measures to meet new safety regulations in the wake of the Fukushima accident. For assuring the seismic safety, various measures were taken such as the exhaustive evaluation to prove the sufficient seismic resistance and the reinforcement works to improve the seismic performance. As a representative example, the seismic safety measures used for Mihama unit 3 are reviewed and summarized in this paper. Also, the future expectations for the development of the seismic design methods and the seismic retrofitting measures are described briefly.
At nuclear power plants, various actions have been conducted to meet the new Japanese regulatory requirements to improve nuclear safety. This paper presents the current status of the seismic design methods and the safety enhancement actions for the BWR nuclear power plants of the Chugoku Electric Power Co., Inc. By way of a representative example, the countermeasures used for Shimane unit No.2 are summarized including the advanced seismic design methods. Also, the future expectations for the development of the seismic design methods are described briefly.